A Monolithically Integrated Silicon Photonics 8×8 Switch in 90nm SOI CMOS

This work presents the first fully packaged silicon photonics 8×8 switch with monolithically integrated electrical control circuits in 90nm SOI CMOS. The switch is a strictly non-blocking network built from 2×1 and 2×2 Mach-Zehnder switches (MZSs). 180 DACs tune the MZSs and 112 ADCs measure optical power across the network for feedback control. Digital interfaces provide low-speed tuning/monitoring and high-speed switching controls. 5.6ns optical switching is achieved with thermo-optically tuned crosstalk <-33.5dB.